Key boabd fob musical instruments



(No Model.) v 2 Sheets--Shee I. A. L. KROM.

KEY BOARD FOR MUSIGAL INSTRUMENTS.

No. 367,148. Patented July 26, 1887.

(No Model.) 2 Sheets-Sheet 2.

A. L. KROM.

n KEY BOARD FR MUSICAL INSTRUMETS.y No. 367,148. Patented July 26,1887.

N. PUERS, Pfwlnumoghymr. wmhingmnE D.c. l u

UNITED STATES PATENT OFFICE.

ANDRnAs LoDEwi'K Knorr, 0E UTRECHT, HOLLAND.

KEY-BOARD-FOR MUSICAL INSTRUMENTS.

SPECIFICATION forming part o f Letters Patent No. 367,148, dated July 26, 1887.

Application tiled May 6, 18.87. Serial No. 237,290. (No model.) Patented in Germany J'uly l5, 1886, No, 40,046; in England March 8, 1887, No. 3,48l, and in Belgium March 10, 1887, No. 76,642.

T0 LZZ whom it may concern.-

Be it known that I, ANDREAS LODEWS'K KROM, manufacturer, subject of the King of Holland, residing at Utrecht, No. 124 Schoutenstraat, Holland, have invented certain new and useful Improvements in or applicable to Piano-Fortes and Like Instruments,(for which Letters Patent have been granted in Germany, No. 40,046, dated July 15, 1886; Belgium, No. 76,642, dated March 10, 1887, and Great Britain, No. 3,481, dated March 8,18875) and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification. f'

Referring to the drawings, Figure l is an endelevation ofso much of an upright piano as is necessary to illustrate my invention. Fig. 2 is a vertical section of Fig. 1; and Fig. 3 is a section' taken on or about on line :c x of Fig. 2, showing the keyboard reversed with the bank of keys b in their operative position. rlhe difiiculties encountered by teachers in teaching the younger pupils to play on the piano or other similar key-instrument are well understood. These difficulties arise, chieiy, from thelimited stretch ofthe pupilstingersthe stretch of an-octave,.for instance, on the ordinary keyboard being too great for a child. The means heretofore proposed to remedy this diiiiculty, by supplying interchangeable key-n boards the bank of keys which vary in range, are very complicated and costly and require skill and experience in effecting the changes. The object of my invention is to remedy this difficulty; and it consists in a reversible key-board having two banks of keys varying in range and interchangeable relatively to the action or mechanism that operates the soundproducing devices, as hereinafter fully described, and as set forth in the claims. A

In the drawings, el indicates a portion of the ends and the cheeks of the framing of an upright piano, in which cheeks is formed a groove, d', and A indicates the key-board provided at its ends wit-h pivots i, that have their bearings in the end boards of a sliding frame,

c. Each end board of the frame c is provided with a tongue, e, that fits into the groove d in the cheeks ofthe piano-frame, so that said frame c can be drawn out and pushed back into the main frame and so that the said key-board A, when the frame is fully drawn out, can be reversed by rotating the same on its pivots z'.

Upon one face of the key-board Ais arranged the usual bank of keys, a, and upon the other face a bank of keys, b, of a less eX- tent of range, but containing the same number of octaves, the keys b being made much narrower than the keys a to reduce the distance between the extreme keys of an octave or that between any two keys, so as to correspondingly reduce the stretch of the fingers. To obtain this result, the keys b are necessarily made to diverge from the center of the key-board to the opposite ends thereof, as shown in Fig. 3, in order to bring the inner end of thekeys under their respective actions, the banks of keys a and b being reversely mounted on the key-board, so as to bring the voperative ends of the keys in proper position after the key-board A has been swung aroundv to bring the bank of keysb in the place of the bank of keys a, Fig. 2, for instance, or vice versa.

The pivoted key-board frame A, Fig. l, is shown as fully drawn out and part-ly swung around on its pivots to bring the bank ot' keys b into the place of the bank of keys a.

If desired, the sliding frame c may be dispensed with, and the key-board A may be made to slide in and out of the pianoframe, in which case the pivots t' of the key-board will have their bearings and slide in the grooves d in-the piano-frame ,or the keyboard A may be arranged to be completely Withdrawn from the pianoiraine and reversed bodily, in which case said key-board maybe provided witha tongue that fits and slides in the groove din the ends or cheeks of the frame.

Ot' course a plurality of key-boards, each having one bank of keys only, and constructed to be interchangeably applied to the instrument, may be employed.

Having now described my invention, what I claim, and desire to secure by Letters Patent, 1s

IOO

1. In musical instruments provided with a l key-board and keys, the combination, with the action or mechanism that operates the sound-producing devices, of a reversible keyboard, as described.

2. In musical instruments provided with a key-board and keys, the combination, with the action or mechanism that operates the soundw producing devices, of a reversible key-board provided with two banks of keys varying` in range, arranged on the opposite faces of said board, substantially' as and 'for the purpose specified. 3. In musical instruments provided with a key-board and keys, the combination, with the action or mechanism that operates the soundproducing,r devices, of a reversible key-board provided with two banks ol' keys varying,` in range, but having the same number of octaves, arranged on opposite faces of said board, sub stantially as and for the purpose specified.

4. In a musical instrument provided with a key-board and keys, the combination, with the frame of the instrument and the action orb mechanism that operates the sound-producing devices, of the sliding' frame c and the keyboard A,pi voted in said frame, said key-board being provided with two banks of keys, a and b, one on each of its faces, substantially as.

and for the purpose specified.

In testimony whereofI affix my signature in presence of twowitncsses.

ANDREAS LODEWYK KROM. VitneSses:

A. S. VocEN, XV. KABAN. 

